Aircraft deviation indicator



Aug. 20, 1935. A. URI-'ERy 2,011,738A

l AIRCRAFT DEVIATION INDICATOR Filed Deo. 19, 1931 i IN VEN TOR. ,400m Uff-fe by means of a single pointer.

Patented Aug. 20, 1935 omiso. STATES AIRCRAFT DEVIA'rIoN INDICATOR.

Adolf Urfer, Richmond Hill, N. Y., assignor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application December 19, 193i, Serial No. 582,145

16 Claims.

The present invention relates to indicating devices, and more particularly to an instrument for indicating the attitude of an aircraft with respect to two oi its axes while the craft is in ight.

The invention embodies an indicator or pointer carried by a .gyroscope having three degrees of freedom and rotated about an axis parallelto the longitudinal axis of the craft and arranged to be actuated upon movement of the craft about two of its axes at right angles to each other.

More speciiieally, the instrumentl embodying the invention isprovided ior'the purpose of indicating the pitching and turning of an aircraft, Such instruments are generally known in' the art as deviometers. Deviometers oi the prior art, however, have been found to be more or less ineflicient due to the;

fact that they are arranged so that the pointer thereof returns to its nonnally'eentralized position rapidly'and almost instantaneously after being actuated by a turn of the aircraft about one oi' the-'two axes, and consequently, with such de- I vices the pilot may make a turn or an inclination which he would not be aware of unless he had his eyes on the instrument continuously, because the instrument may have been actuated while his shaft. The rate oi return of the pointer to normally central positlonis a function of the torque 'and is practically imprimible to adjust.

. element thereof whereby vthe driving torque on the element isluniform and which is independent of the universal support of said element.

Another object is to provide in a deviometer embodying a gyroscopic element having a pointer,

thereonnovel centralizing means wherebythe pointer may be returned to a normally centralized position at a predetermined and gradual rate.

A Afurther object of the invention is to provide in a deviometer embodying a universally supported gyroscopic element having a pointer thereon, novel means whereby the rate of return of the pointer to its normally centralized position may be adjusted to any desired degree.

Still another object is to provide in a deviometer, a novel construction whereby the pointer remains relatively non-rotatable with 4respect to the gyroscopic element with whichA it is associated and whereby the gyroscoplc element is driven independently of the pointer and of its universal support. 1

A still further object is to provide in a devometer of the class described andhaving a pointer cooperating with a dial and arranged to vbe actuated within the Vrange of the dial, novel 20 means whereby the pointer is prevented from osclating over the dial when it has exceeded a predetermined angular indication.

A still further object of the invention is to provide in a deviometer of the class described, novel means whereby the pointer may be centralized immediately and independently of the slowly centralizing means referred to above.

The above and other objects and. advantages of the invention will appear more fully hereinafter from a consideration of the detailed description which follows, taken together with the accompanying drawing, wherein is illustrated one embodiment of the invention. Itis to be expressly understood, however, that the drawing is for the purpose of illustration and description only, and is not designed as a denition of the limits of the invention, reference being had for this purpose to the appended claims.- A

In the drawing, wherein like reference char- 40 acters refer to like parts throughout the severaly views,

Fig. 1 is a longitudinal section of one form of instrument embodying the present invention;

Fig. 2 is a front view of the instrument-with a 45 portionof the combined dial and cover-glass removed, showing the novel means for preventing oscillation of the pointer when it has exceeded its limit`of travel; and

- Fig. 3 is a front view showing the dial and the 50 relation of the pointer thereto in its normally centralized position. Y

Referring to-the drawing, and more particularly to Fig. 1, .the deviometer embodying the' present invention comprises an air-tight casing 4 provided with an annular ange 5 for mounting the instrument on a panel by means of the lugs or eras 6. The gyroscopicA element is constituted by a rotor I having turbine buckets 8 and journaled on a relatively stationary shaft 9 in any suitable manner, as by means of roller bearits universal support, as pointed out hereinbefore,A

ings III and II. A

Means are provided for driving the rotor 'I on its shaft 9 by means of an air-stream impinging against the buckets 8 as in a steam turbine, and

in the form shown comprise nozzles I2 and I3 which are secured to the wall of the casing 4 in.

- any suitable manner, as for example by threaded IIS4 ' shown, the universal mounting comprises a gimengagement therewith. The air-streamthrough the nozzles I2 and I3 is provided by means of creating a suction within the casing in any manner desired, as by a suction pump (not shown) or by a Venturi tube I4 connected to a pipe I4a secured to the casing as by means of the coupling member I and the nut I6. It will beapparent that as air is withdrawn from the casing by means of the Venturi tube I4 through the pipe I4a, a supply of air will enter the casing from the exterior thereof through the nozzles I2 and I3,v

thereby impinging on the buckets 8 and imparting rotation to the rotor I on the shaft 9 throug the roller bearings I0 and II.

'Ihe shaft 9 is universally supported on a rigid tubular member I 'I which may be secured to or formed integral with the casing 4. In the form bal ring I8 pivoted von the member Il on an axis passingv through its center at right anglesto the plane of the drawing, and pivotally connected to the gimbal ring is a funnel-shaped i extension 28 of the shaft 9, as by means of the pivots 2| and 22, which coincide with an axis perpendicular tothe first mentioned axis. The rotor 'I is arranged in such a manner and designed to be of such weight that, together with the shaft 9, it will have its longitudinal axis perfectly balanced on the gimbal ring I8. It will be seen that when the rotor I is brought upto a predetermined speed, the gyroscopic eiect thereof will tend to maintain its axis stationary when4 the casing 4 is turned about`a vertical axis or about an axis perpendicular to the plane of the drawing lcorresponding to a turn and a. pitch, respectively, of an aircraft on which the casing is mounted, thereby producing relativer-:angular movement between the rotor and the casing.

For example, if the craft is flying in the direction l of vthe arrow 23 and inclines upward, the relative movement of the shaft 9 on its universal support will be upward, and if the craft inclines downward, the relative movement of the shaft 9 with respect to the casing will also be downward about the horizontal axis of the gimbal ring I8. In the case of a turn of the craft to the left or right, the relative movement of the shaft 9. will also beto the left or to the right with respect to the casing.

Means vare now provided for employing the relative movements of the shaft 9 with respect to the casing to produce visible indications of such movements, thereby indicating the attitude of the craft, and in the form shown comprise a pointer 24 secured to or formed integral with theshaft 9 and cooperating with a dial 25 which also forms a cover-glass for the instrument. The combined dial and cover-glass 25 may be secured tothe front o f the casing 4 in any suitable manner, as by means lolf a ring 26 and screws 21. Etched on the cover-glass 25, or marked thereon in any other suitable manner, is a vertical line 28 and-a horizontal line 29 intersecting each other at 30, the intersection being the normally central position of the pointer 24, and coinciding with the longitudinal axis of the rotor I and theshaft 9.

Since the gyro-rotor 1 is not driven through shaft 9 by means of supporting members 35, 36, Y

3l, and 38 carried by the shaft 9. Cooperating with the vanes 3|, 32, 33, and 34 are jets 39, 48, 4I, and '42, respectively, through which a stream of air is introduced into thecasing from the eX- terior of the latter in the same manner as the stream which drives the rotor 'I. The vanes on the jets are SUO-arranged that when the shaft 9 isV in its normally central position, the air-stream downward, or to the left or right, due to a change in the position of the gyroscope axis by virtue of a pitch or turn of the craft, one of the plates will' move into the air-stream of its associated jet,l as

for example, if the pointer moves upward, theplate 3| will move into the air-stream of the jet 39. 'I'he action of the air-stream from the jet 39,'

on the plate 3I will tend to move the gyro axis to the left, but in so doing a precessional force is' created which moves the gyro-axis,and consequently the pointer 24, downward until the plate 3l is again clear of the air-stream. If the pointer moves -downward the plate 32 then 'is moved into` the air-stream of the jet 40, tending to move the gyroscope axis to the right, thereby producing a precessional force which moves the pointer upward until the plate orV vane 32 is clear of the airstream. The samel action takes place by means,

of the vanes 33 and 34 when the pointer moves to the left or to the right, respectively; or if a compound motion is imparted to the pointer 24 so that it is Amoved in two directions simultaneously, two or more of the jets will then direct a stream of air on their associated plates to produce the required precessional forces for returning the pointer to its normally-centralized.position. The pointer returns to its normally centralized position sub- 2. from each of the jets just clears each associated f5'. vane so that no action is produced on the vanes.y

However, if the pointer 24 moves upward or stantiallyon a straight line and will return very gradually without any oscillation of .the pointer. 'I'he rate of return can be easily varied by changing the size of the jets 39, 40, 4I, `and 42.*, The latten/are removable, and for this purpose are provided with threaded portions A43Vv and a nut 44 so that they may be screwed into the. wall of the casing 4. It will be apparent, however, that the air-stream of the jets may also be varied by providing a suitable valve arrangementfor each of the jets to increase or decrease the ow of air therethrough. It wilt-,be apparent from the fact that the centralizing varies and-air jets are independent of the driving means of the gyroscopic ele- ,ment, that no matter what the driving force is on the latter, the centralizing force can,b e adjusted so as to obtain any desired rate of return of the pointer. When this adjustment is made, then the rate of return of the pointer remains fixed unless readjusted again, even though the -suction normes 3 through the Venturi' tube Id increases, because the velocity of air will increase through the centralizing jets 35, di), 4i, and 42 as well as through the nozzles i2 and i3. Hence, the ratio of the o centralizing force and the driving force will remain constant for any particular adjustment of the air'jets.

from the particular arrangement ol' the pointer 2d with respect to the interior of the casing, it

lo will he seen that if the pointer is moved beyond a predetermined limit, 'as deilned by the wall oi the casingit will strike against the casing', and unless some means are provided for stopping the pointer,

an undesirahleoscllation thereof would be proll duced and accordingly, novel means are provided for eliminating suchV oscillations. In the torni shcwn,said means comprise toothed racks4 45, 4B,

di, and "i3 arranged in the form oi a square and secured to the casing in any suitable manner, as

20v hy means of screws 9. Arranged to,.cooperate with the teeth or serrations B of the racks It, 4t,

41, and t5 are four pins 5i, 52, 53, and 54 carried on a bushing *5t which is mounted for limited rotational movement on the shaft of the pointer 2d.

25V The limited rotational movement ci' the bushing 55 is determined hy means of a slot it thereon and a pin 5l carried by the pointer shalt. it coil spring 53 is provided for counter-acting the rotation of the bushing 55 and has one end connected no to said bushing and the other end to the shaft t.

The teeth or serrations 5t are inclined in the direction of rotation of the rotor i, so that when the pointer 25 is moved to its limit upward or downward, or to the leit or right, the pins Si, t2, as 53; and 5d will follow into one of the serrations of their associated racks 45, 4t, di, or do. Since the pins would strike their corresponding racks with some force, they would tend to br oit, but

by means of the coil spring 5t, such breaking is 4@ prevented, because the shock is taken up by the winding up of the spring by the limited movement of the bushing 55 through the slot and pin connection 5S and 5l. By the winding action o the spring 53, a force is produced which tends to 5 move the pin out of the serration after the air- A craft has ceased turning or pitching, thereby permitting the varies 3l, 32, 33 or M to gradually return the pointer to its normally centralized position.

5@ Under certain conditions, it is desirable to be able to .centraline the gyro instantaneously.

This is especially true in starting the'device in operation and after a violent maneuver oi the aircraft on which the device :ls/mounted, daring 55 which time the position of the pointer is questionahie. To this end, a novel rapidly-centralizing unit is provided to permit centralizing of' :the pointer from the front of the instrument independently of the action oi the centralizing @9 venes, and, in the forni shown, comprise means including the :tunnel-shaped extension 29 of the shaft 9 and a rod or pin 59," which is arranged to enter a cylindrical opening it provided in the egtension 2li. The rod 59 maybe actuated d5 to enter the opening @t in any suitable manner, as by means of a bell-crank tl pivoted at t2 and connected to anoperating lever dll which extends. to' the front of the instrument and is Y, providedwith a knob 6d. The rod or pin iid 70 passes through the gimbal supporting member il and is provided with an enlarged portion @Si which is arranged to operate in the manner of a piston .in sa cylindrical chamber tt iced in the member il, and a spring 'i is interposed 55 between the enlarged portion Si and the wail oi.' the cylinder BG for normally maintaining the pine out of the cylindrical opening l0 until Such time. as the pin is actuated against the spring 6l by means of the bell-crank 6I and operating lever 63. 5

There is thus provided a novel-instrument for indicating the pitch and/or turn of an aircraft on which it is mounted whereby a prolonged indication is produced after the pointer has been actuated and the craft has ceased its turn and/or 10 pitch, and whereby the pointer is gradually returned to its normally centralized position at any predetermined rate ofreturn.

Novel means are also provided whereby breaking of the pointer is prevented when it has exl5 ceeded its limit of travel.

Although only one embodiment of the invention has been illustrated and described, other changes and modifications in form and relative arrangement of parts, which will now appear V to those skilled' in the art, may be made without departing from the scope of the invention. For example, the gyroscope rotor may be driven from the intake manifold of the engine of theaircraft as well as from a vacuum or pressure pump or from a Venturi tube. Also, the gimbal ring y i8 comprising the universal mounting for the rotor may be replaced by any other suitable type of universal joint permitting angular movement of the rotor shaft in any direction. The ind1- 30 vidual serrated racks d5, It, 4l, and 48 maybe replaced by a single frame, either circular or v square, having serrations on its inner periphery and inclined in the direction of rotation of the gyroscopic element. Reference is therefore to .35 be had to the appended claims for a definition of the limits of the invention.

t is claimed is:

i. A deviation indicator comprising in combination, 'a casing; a non-rotatable shaft having o a hollow conical extension at one end and a pointer at the` other end; a support for said shaft carried by the casing on the same longitudinal axis with said shaft, said shaft being normally in alignment with said support; a gimbal ring interposed between said shaft and lsaid support and located within the conical extension Y of said shaft so that the latter may incline about two axes at an angle to each other in the same pionera gyroscoperotafably mounted on said 56 y of the :drst mentioned centralizing means, said` rapidly centralizlng means comprising a rod arranged to engage the hollow end of the nonrotatable shaft, and means operated from the iront of the casingfor actuating said rod into engagement with said shaft.

2. A deviation indicator comprising in combination, a casing; a non-rotatable shaft having aipointer at one end thereof; a support for said m shaft carried by the casing, said shaft being normallyin alignment with said support; means interposed between said shaft and said support so that said shaft can incline at an angle to the longitudinal axis of thecasing; a gyroscope 715,'

rotatably mounted on said shaft for maintaining the latter normally in alignment with its sup-- i5 preventing oscillations of the pointer when the latter exceeds a. predetermined angle of inclination; and means independent of the driving means for returning the pointer and shaft tonormally centralized position at a predetermined frate after an inclination thereof.

3. A deviation indicator comprising in combination, a casing; a non-rotatable shaft having a pointer at one end thereof; a support for said shaft carried by the casing, said shaft being normally in alignment with said support; means in ,terposed between the other end of the shaft and said support for universally mounting said shaft for movement about two axes perpendicular to each other in the sameplane; a gyroscope rotatably mounted on said shaft and adapted to move therewith; means for driving said gyroscope; means associated with said pointer and said casing for preventing oscillations of the pointer when the latter'exceeds a predetermined angle of inclina- ;tion, said means comprising a plurality of serrations carried by the casing and pins carried by the pointer for engagement with said serrations; and means vfor returning said gyroscope and pointer to normally centralized position at a preidetermined rate independently of vthe drivin torque of the gyroscope.

4. A deviation indicator comprising in combination, a gyroscope universally mounted for movement. about three axes perpendicular to each `other; means for driving .said gyroscope whereby Vthe axis of rotation thereof tends to remain fixed ing means and unaiected thereby for returning' said gyroscope to its original normally centralized position with respect to the fixed support at a predetermined and selected relatively slow rateV independent of the driving torque of the Agyroscope when relative movementbetween the gyroscape and-the supportgabout both of said two rst mentioned' axes has taken place. i

5. A deviation indicator comprising in combinatlon, agyroscope universally mounted for movement about three axes at an angle to each other; iiuld pressure means for driving said gyroscope whereby the axis of rotation thereof tends to re- .main xed in space; a fixed support for said gyroscope relative to which the rotational axis of the gyroscope is adapted to incline upon movement of the support about either or both of two of the vi'lrst mentioned axes; and i'luid pressure means 'independent of said driving means for returning saidgyroscope to its original normally centralized position with respect to the xed support at a predetermined-and selected relatively slow rate produced by a force which is maintained in a` Aiixed predetermined ratio to the force driving the' gyroscope whenl relative movement between; the

gyroscope and the support about both of said two first-mentioned axes has taken place. 6. A deviation indicator comprsingin combination, a gyroscope universally mounted for movementY about three axes at an angle to each other; fluid pressure means for driving said 'gyroscope about a horizontalaxis whereby said axis tends to remain iixedin space; a fixed support for said gyroscope normally in alignment with said horizontai axis but aaa'p'ted'to be inclined relative thereto about either or both of two of the rst mentioned axes while the third axis remains in its xed horizontal position; and means effective upon an, inclination of the fixed support for returning said gyroscope to its original normally centralized position with respect to the xed support at a predetermined andselected relatively slow rate produced by a force which is maintained in a fixed predetermined ratio to the driving force of the gyroscope by the precessional force of the latter produced by its-return movement when relative movement between the gyroscope and the support about both of said'two first-mentioned axes has taken place.

'7. A deviation indicator comprising in combination, a gyroscope universally mounted for movement about three axes perpendicular to each other; fluid-pressure means for driving said gyroscope about one of said axeswhereby the latter tends to remain iixed in space; a fixed support for said gyroscope normally in alignment with said rotational axis but adapted to be inclined relative thereto labout the two remaining axes of said gyroscope; and iuidpressure means independent of said driving means for returning the rotational axis .ofthe gyroscope into alignment with the iixed supportat a predetermined rate, said means comprising a plurality of vanes radially disposedabout the rotational axis of the gyroscope, and means for directing a jet of i'luid onto one or more of said vanes upon relative inclination between the gyroscope and vits fixed support whereby precessional forces are produced to bring said axis in alignment with the support.

8. A deviation indicator comprising in combination, a gyroscope universally mounted for movement about three axes perpendicular to each other; iiuidpressure means for driving said gyroscope aboutone of said axes`whereby the latter tends to remain fixed in space; a relatively xed support for said gyroscope normally in alignment clined relative .thereto about the two remaining axes of said gyroscope; and fluid pressure means independent of said driving means for returning the rotational axis of the gyroscope into alignment with the f ixed support at a,v predetermined rate, said means comprising two pairs of vanes radially disposed about the rotational axis of the gyroscope and each pair being in a plane perpendicular to the plane-of the. other pair, and means.

adapted to be rotated; uid pressure means yfor driving said gyrOscope on said shaft whereby the latter tends toremain xed in space; a'relatively xed support for said 'shaft normally inbalignment with the latter but adapted to be inclined relative thereto about the two remaining axes of said gyroscope; a pointer carriedby. said shaft and adapted to indicate the relative inclination thereof with respectto the xed support; and uid pressure means independent of said driving means for'returning the non-rotatable shaft into with said rotational axis but adapted to be inof said axes and upon which the gyroscope is alignment with the fixed support at a predeter- 75 mined rate upon a relative inclination therebetween, said means comprising two pairs of vanes carried by and radially disposed about the. shaft and one pair lbeing in -a plane perpendicular to the plane of the other pair,` and means associated with each of said varies for directing a jet of fluid thereto upon relative linclination between the shaft and the fixed support wherebypre'- said gyroscope -on saidshaft whereby the lattercessional forces having a fixed ratio to the driving force on the gyroscope are produced to. bring -said shaft in alignment with said support.

10. A deviation indicator comprising in combination, a gyroscope universally mounted for movement about three axes perpendicular to each other; a non-rotatable shaft coinciding with one of said axes, said gyroscope being mounted for rotation thereon; fluid pressure means for driving tends to remain in a xed position; a relatively fixed support'for saidshaft normally infalignment with the latter but adaptedgto be inclined relative thereto aboutthe two remaining'axes of said gyroscope; universal joint means connecting said shaft and support; means on said shaft for indicating the' relative inclination between the gyroscope rand the fixed support; and fluid pressure means associated with said fixed support and said non-rotatable shaft but independent of said driving means for returning the non-rotatable shaft into central position with 'respect'to the fixed support at a predetermined rate and effective upon a relative inclination there-between.v

a universal support secured to 'the casing and- .carrying one end ofthe shaft; a gyroscope rotat- 11. A deviation' indicator comprising in coml bination, a casing; anon-rotatable shaft therein; a support-.carried bythe casing; means connecting one end of the shaft to said support for universal movement; a 'gyroscope rotatably mounted on said shaft; an indicator operated by the shaft; andmeans effective upon relative,

movementbetween the shaft and its support for centralizing the gyroscope and the indicator.

12. Al deviation. indicator comprising in c'mblnation, a casing; a non-rotatableshaft therein;

.a' universal support for said shaft and secured to one end thereof; a gyroscoperotatably mounted on said shaft; uid pressure means for driving .said gyroscope; an indicator operated by the gyroscope;I and fluid pressur 'means for cent'l'alizinglA the gyroscope and thein ticating means-,saidlen tralizing means comprising a plurality of varies carriedby and radially disposed about the nonrotatable shaft, and means for directing a'jet o f fluid pressure onto said vanes.

13,.' A deviation' indicator. 4comprising in cornbination, a casing; anon-rotatable shaft therein:

a universal support secured to the. casing and carrying one end of the'shaft; a gyroscope rotatably mounted on said shaft; a pointer carried by ..port. f

ablyI mounted on said shaft; a pointer carried by said shaft and adapted for inclination therewith relative to the casing; air operated means associated with -the casing andthe shaft for centralizing the gyroscope and the pointer; and

means carried by the casing and cooperating with the pointer for preventing oscillations of said pointer when the latter strikes the casingupon an'excessive inclination thereof, said means comprising' means carriedby the casing and having serrations therein, and a plurality of pins carriedby the pointerand adapted to engage the serrations when the pointer strikes the wall of the cas-V 15. A deviation indicator comprising in combination, va. casing; 'a 'non-rotatable shaft therein; a universal support secured to the casing and carrying one. end of the shaft; a gyroscope rotatably-mounted on said shaft; a pointer carried by the other end of said shaft and adapted -for inclination therewith relative tothe casing;

meansassociated with the casing and the *shaft for centralizing the gyroscope and the pointer;

land means carried by the casing and cooperating with the; pointer for` preventing 'oscillations of said pointer when the latter strikes the casing', s

upon exceeding a predetermined angle of inclination, said means comprising means carried by the casing and lhaving seri-ationsr therein, a plurality of pinscarried by the pointer and adapted toengage the serrations when the pointer strikes the wall of the casing, and resilient lmeans inter- 'posed between the pointer and the pins for taking up the limpact o'f the pointer, against the casing andgfor withdrawing thepins saidsupport for'universal movement; a gyroscope, rotatably mounted on said shaft; andmeans effective upon relative movement between the shaft andgyroja'nd its support for, automatically. cen`" tralizing. the gyroscope ,withn respect to said sup- Q'QADoLF v 16.- A gyroscopic device comprising incombination, a non-rotatable shaft; a support for said shaft;- means connecting one end of ,the shaft to 

